Self-adjusting feed mechanism



(No Model.) 2 Sheets-Sheet 1`.`

C. A. JUBNGST. SEEE ADJUSTING FEED MEGEANISM.

No. 512,972. f1.5 ,Patented Jan. 1.6, 1894.51

1 WIM/55155 M.

, Ajman-Y UNITED STATES PATENT OFFICE.

CHARLES A. JUENGST, lOFCROTON FALLS, NEWY YORK.

SELF-ADJUSTING FEED MECHANISM.

SPECIFICATION forming part of Letters Patent No. 512,972, dated January16, 1894.

Application led March 6,1893. Serial No. 464,641. V(No model.)

cially that class 0f such mechanism whereinv the speed of the screwvaries with the resistance oered by the work as for example a rail-roadrail to the advance of the tool.

My invention consists of the novel features hereinafter set forth, andillustrated in the accompanying drawings, in which- Figure I representsan end view of a sawing machine to which it is applied. Fig. II

. represents a sidevview of a portion thereof.

Fig. III represents a vert-ical cross section on theV line Fig. II. Fig.IV represents a partial top View and partial horizontal section of themachine.

Similar letters of reference indicate similar parts.

The letter A indicates the bed of the machine, resting on the frame B,in which is loc ated the traveling tool carriage C. This carnage C, maybe of'any usual or""suitable construction, and it is mounted on the feedscrew D, to receive the required motion therefrom, and also upon apower'shaft c, from which motion is transmitted to the saw F, or othermachine-tool on the carriage; the screw and shaft both extending thewhole length ofthe machine.

Referring to the feed mechanism, the letter G, indicates a cog wheel,which is made fast on the feed screw D, at one end of the machine; H apinion, which, under normal conditions, meshes with the cog wheel; I amain pulley, which is firmly secured to the pinion, it being alongsidethereof; :I an arbor, Which carries the pinion and main pulley; K aswinging arm, which forms a bearing for the arbor; N a driving pulley,and O a belt connecting the two pulleys. In the example shown, thedriving pulley N, is mounted on the power shaft e, and it, as well asthe main pulley I, is flanged for retaining the belt O thereon; whilethe belt is crossed for reversing the direction of motion of thepulleys.

The swinging arm K is hung on the feed screw D, through the medium of aneccentricv P, receiving a hub Q, of the arm, for the purpose hereinafterexplained; and at a point below the arbor' J ,.the arm has a hole K (seeFig. Il) for the engagement therewith of one end of a rod R, which ishung at its other end to a pivot s, or other proper support on themachine, the rod having a head R to receive the pivot. On the rod R, isa spirial spring U, which acts on the swinging arm K, witha tendency toforce the main pulley I, away from the driving pulley N, namely, byforcing the arbor J, in that direction; on the rod being also a screwnut W, which engages the spring, bringing the latter intermediate ot'the swinging arm and nut; a portion of the rod being threaded to receivethe nut. I

The operation of the feed mechanism thus formed, is as follows: Motionis transmitted from the driving pulley N, t0 the main pulley I, by thebelt O, and thence throughthe pinion H, and cog wheelv G, to the feedscrew D; and by the action ofthe spring U, the belt O, iskept normallyin a state of tension, with the 'edect of rendering the motion of thefeed screw uniform and comparatively high in rate of speed. lf now thework presented to the saw F, varies in its bulk or thickness, offering avarying resistance to the advance of the saw, the greater resistancethus offered causes the carriage C, to exert a back pressure on the feedscrew D, and retard its motion, together with that of the cog wheel G,whereupon the pinion H, begins to roll on the cog wheel in the directionof the arrow in Fig. I, and against the action of thesspring U, reducingthe distance between the pulleys I, N, and slackening the belt O; theresult being to lessen the speed of motion of the feed screw and producea comparatively slow advance of the carriage. The tension of the springU, can be regulated by means of the screw nut W, causing it to exert agreater or lesser pressure on the swinging arm K, according to thenature of the work in the machine.

The eccentric P is loose on the feed screw D, and it usually has ahandle P for conven IOS ience of its adjustment; while the hub Q, of4

the swinging arm, is loose on -the eccentric, as more clearly shown inFig. Ill. By rocking the eccentric P, on the feed screw, it acts on thehub Q, to raise or lower the swinging arm K; and in the lower positionof this arm the pinion l-l, is thrown out of gear with the a weight orany other suitable tension device may be employed to act on the swingingarm,`

`or its substitute.

lrVhat I claim, and desire to secure by Letters Patent, is-

1. Afeed mechanism for a machine-tool carringe,- comprising a feedscrew, a cog wheel fast thereon, a`pinion meshing with .the cog wheel, ameausfor driving the pinion, with a belt, and a tension device operatingto keep the belt normally ina state of tension, substantially' asVherein described.

l `2. ,In combination with a machine-tool carriage, the feed mechanismcomprising a feed screw, acog wheel fast thereon, a pinion meshing withthe cog wheel, a main'pulleysecured tothe pinion,an arbor carrying thepinionand main pulley, a movable bearing for the a arbor, a drivingpulley, a belt connecting the two pulleys, and a tension device actingon the movable bearing to force the main pulfley away from the drivingpulley, keeping' the belt normally in a state of tension,.substantiallyas-herein described.

3; -In combination with a machine-tool carriage, the feed mechanism`comprising a feed screw, acog wheel fast thereo'n, a pinion meshing with`tfhecog wheel, a main pulley secured t0 the pinion, an arbor carryingthe pinion and main pulley, a swinging arm on the feed screw, forming abearing for the arbor, a

driving pulley, a belt connecting the two pulleys,a rod hung to a propersupport at one end and engaging the swinging arm at the other or freeend, a spiral spring on the rod, acting on the swinging arm to force themain pulley away from the driving pulley, keeping the belt normally in astate of tension, and a screw-nut on a threaded portion of the rod,engaging the spring, for regulating its tension, substantially as hereindescribed.

4:. In combination with a machine-tool carriage, the feed mechanismcomprising a feed screw, a cog wheel fast thereon, a pinion meshing withthe-cog wheel, a main pulley secured tothe pinion, an arbor carrying thepinion and main pulley, an eccentric` loose `on the feed screw, aswinging arm forming a bearing for the arbor, with a hub loose'on theeccentric, adapting the pinion to be thrown out of gear, a drivingpulley, a belt connecting the two pulleys, and a tension device actingon the swinging arm to force the main vpulley away from the drivingpulley, keeping thebelt normally in a state of tensi n, substantially asherein described.

5. `In combination with a machine tool carriage, the feedmechanismcomprising a feed screw, a cog wheel fast thereon, a pinion meshing withthe cog wheel, amain pulleysecured to the pinion,'an arbor carrying thepinion and main pulley, an eccentric loose on the feed screw, a swingingarm forming a bearing for the arbor, 'with a hub loose on'the eccentric,adapting the pinion to be thrown outof gear, a'drivingpulley, a beltconnecting the two pulleys, a rod yhung to a proper support at one endandengaging the swinging'arm at the other or yfree end, a spiralv springon the rod, acting on the swinging arm to Aforce the main pulley awayfrom the driving pulley, keeping the belt normally in a state oftension, and a screw-nut on a threaded portion of the rod, engaging thespring, for regulating its tension, substantiallyasherein de scribed. i

CHARLES A. JUENGST. Witnesses:

CHARLES G. COE, CHAs. WAHLERS.

